95 and 90 Floppy Controller These systems use the Intel 82077AA floppy controller.
The EE floppy drive can be used on them, but the AA does not support the
EE functions.

9577 Bermuda Floppy Controller These systems use either the 82077AA, 82077SL (rare),
or the NS PC8477AV floppy controller. Usually, systems with the NS controller
use "*" marked floppy drives. BUT I have found some 82077AA/* combinations,
plus what I believe to be a late Bermuda with a 82077SL floppy controller
with a * marked floppy on it...

From David Beem Here is the listing of 82077xx FDC chips that are
able to support the 2.88 EHD drives:

1Ed.
All models support the 3.5" Electronic Eject floppy drive. (and 2.88!!)
2Ed.
Known to support 2.88 Note: early 8595s do not support the 2.88MB
floppy
3Ed.
All N-Q support the EE floppy (and 2.88!!)

One pattern seems to emerge from the PS/2 planars:
the "souped-up" or second-gen planars have the 82077SL FDC chips. A couple
of surprises though. I did find two other FDC chips on my equipment. The
first on Bermuda planar #1 is a National Semiconductor 8477AV-2 chip *without*
the "(C) NEC 1979", but with "(C) NSC 1991". Probably a 82077AA replacement
that is reverse enginered enough to avoid having to use the NEC copyright.
That system is unchanged from the way I bought it, with an "*" 2.88 drive.
The spare 2.88 I got on eBay I am unsure of the original model is a non-"*"
drive.
There is a smaller surface mount Intel 82091AA in
my HP NetServer that does bear the "(C) NEC'79" & also "(C) Intel '86
'93". Just a guess again about being a replacement for the 82077AA with
the end of the part number. All the Intel 82077AA and 82077SL chips I have
otherwise have "(C) NEC 1979" & "(C) Intel '86 '91" of course. Other
clone motherboards and adapter cards I have don't look like they have a
stand-alone FDC chip. Most support the EHD drives in the BIOS, so it has
to be a variant of the 82077xx somehow (Even the enhanced NEC 72065B doesn't
support 2.88 drives.).
FDC chips are supposed to give which level they
are by a "ver" command given to the chip. By my reference all flavors of
the 82077 return the same value. I have tried a routine for the FDC ver
command that so far has *not* worked. The PS/2 35SX and 53 486SLC2 planars
both give a return value for a standard FDC that doesn't support 2.88 drives,
then make the computer unable
to read the drive! Here is the (of all things, BASIC) routine anyway
& I am going to keep trying to get it to work.

Formatting
720K Disks on a 1.44MB Floppy>Why don't you use format /f:720 in the DOS window to make the 1.44
disks 720k suitable? Maybe the 720k machine can't read them later, but
this depends on the
drive. 720k drives write wider tracks than 1.44 do.

Peter blearily looks up from
his bowl of Fruit Loops 'n Beer and sez:
Guess I jump in here and clear some misunderstandments.
1. Older PS/2 are non-media sensing - means: whether the
floppy has the right-hand "media type hole" or not doesn't bother these
machines.
2. "Klone Chop-Suey-PCs" use to have FDDs that *do* test
for the media type
hole - and consequently refuse to read from a down-formatted 1.44MB
floppy. You
*need* to use a piece of transparency tape around the front edge and
cover the
hole from the *underside*. This does not have any effect on the older
PS/2s as
explained in 1. above. The "generic" FDDs use a set of switches on
the right
side to test for a) floppy presence and b) presence of a "High Density"
hole.
(2.88MB drives have a third switch that tests for "eXtra Density" hole,
which
sits a bit further away from the lower edge of the floppy). Some older
PS/2
FDDs have the switches too - but they are used for media presence only
- not
for detecting the media type, like e.g. in a Mod. 50/60, 55/65, 70/80
and the
30-286.
3. If you'd closed the media type hole on am actually
1.44MB formatted floppy
and try to format it on a "non PS/2" machine it might complain on a
false
format in a first attempt. You better use a PS/2 (see 1. )
On DOS after 3.x you need to use FORMAT A: /U /F:720 to format to 720KB.
On DOS 3.x you need to use FORMAT A: /N:9 /T:80 to force a 720KB format.

The /U parameter in later DOS (and Win95 DOS box) does
an "unconditional"
format and ignores all data and formats on the floppy. It does a *physical*
format across all sectors and actually writes the 720K structures at
all.
If you would use the /Q parameter the drive would only try to rewrite
the first
sectors with the File Allocation Table (FAT) on that floppy and leave
the rest
untouched - that will not work and will result in a media error anyway.
The /N:9 parameter on older DOS is the difference between
720K and 1.44MB format. Both use 80 tracks (the /T:80 parameter), but 1.44
uses 18 sectors (would be /N:18), while 720K uses half of them -
therefore /N:9.
The *track width* is the same on 720 and 1.44 format -
because both use 80 tracks and the stepper motor does the same step-width
- and the R/W-head gap does not change during the process ... :-)
Once you'd formatted a 1.44MB floppy to 720KB you might
be unable to re-format
the floppy back to 720KB - even if you remove the covering tape from
the media
type hole. 1.44MB floppies use a Ferro-Chrome (FeCr) base material,
which
"holds" the magnetism a bit stronger than the Ferrite-Oxyd (FeO) material
usually used for 720K floppies. The R/W amplifier on generic FDDs might
be
unable to fully erase the 720K format in this case.

Formatting
3.5" to 360KBOnce again, Peter slips up by saying:
Old PS/2 that do not care (much) for the floppy formats
and use an older DOS (like Mod. 50/60, 55/65, 70/80 with DOS 3.3 to 5.0)
can be convinced to format a 3.5" floppy to 360KB with using FORMAT A:
/N:9 /T:40 .... if you then have a machine with a 5.25" drive as well (as
on my good old trusty Mod. 80-A21) you can use DISKCOPY B: A: to make 3.5"
copies from the 5.25" disks onto 3.5".
Interestingly, most machines support 3.5" / 360KB format
and can at least read it.

System to Floppy
Drive List This list does not mean that you cannot use a later drive
on an older system. That is determined by the BIOS of the system. I do
not know the limits of all these models.
EE = Electronic Eject

64F0206 vs. 64F4148From Peter
These have no grey plastic sled undersides but the metal
mounting plate with integrated side rails. I think that's the major difference
between 64F0206 (Peter, don't you mean
64F0204?) and 64F4148 .. if you look into EPRM you will find that all -4148s
are for 35/40, 56/57 and 76/77 - while the -0206 is for the Mod. 85/90/95.

PERPENDICULAR RECORDING
MODE Toshiba has taken the 2 MB floppy and doubled the storage
capacity by doubling the number of bits per track. Toshiba achieved this
by an innovative magnetic recording mode, called the vertical or the perpendicular
recording mode. This mode utilizes magnetization perpendicular to the recording
medium plane. This is in contrast to the current mode of longitudinal recording
which uses the magnetization parallel to the recording plane. By making
the bits stand vertical as opposed to on their side, recording density
is effectively doubled, Figure 1. The new perpendicular mode of recording
not only produces sharp magnetization transitions necessary at higher recording
densities, but is also more stable.

2.88MB
Floppy Construction The 4 MB disks utilize barium ferrite coated substrates
to achieve perpendicular mode of magnetization. Current disks use cobalt
iron oxide (Co-g-Fe 2 O 3 ) coating for longitudinal recording. The barium
ferrite ensures good head to medium contact, stable output and durability
in terms of long use. High coercivity is required to attain high recording
density for a longitudinal recording medium (coercivity specification of
a disk refers to the magnetic field strength required to make an accurate
record on the disk). A conventional head could not be used in this case;
however, the barium ferrite disk has low coercivity and the conventional
ferrite head can be used. The new combination heads include
a pre-erase mechanism, i.e., the ferrite ring heads containing erase elements
followed by the read/write head. These erase elements have deep overwrite
penetration and ensure complete erasure for writing new data. The distance
between the erase elements and the read/write head is about 200mm. This
distance is important from the floppy disk controller point of view and
will be discussed in later sections.

Gap2 Differences The implementation of 4 MB drives requires understanding
the Gap2 (see Figures 2a and 2b) and VCO timing requirements unique to
these drives. These new requirements are dictated by the design of the
``combination head'' in these drives. Rewriting of disks in the 4 MB drives
requires a pre-erase gap to erase the magnetic flux on the disk preceding
the writing by the read/write gap. The read/write gap in the 4 MB drive
does not have sufficient penetration (as shown in Figure 4a) to overwrite
the existing data.
In the conventional drives, the read/write gap had sufficient
depth and could effectively overwrite the older data as depicted in Figure
4b. It must be noted that it is necessary to write the conventional 2 MB
media in the 4 MB drive at 500 Kbps perpendicular mode. This ensures proper
erasure of existing data and reliable write of the new data. The pre-erase
gap in the 4 MB floppy drives is activated only during format and write
commands. Both the pre erase gap and read/write gap are activated at the
same time.
As shown in Figure 4a, the pre-erase gap precedes the
read/write gap by 200mm. This distance translated to bytes is about 38
bytes at a data rate of 1 Mbps and 19 bytes at 500 Kbps. Whenever the read/write
gap is enabled by the Write Gate signal the pre-erase gap is activated
at the same time.

2.88MB Floppy
source There is a outfit called WSG
Group (site is under heavy construction) that is a high volume diskette
supplier. They currently have over 600,000 finished, ready to go
diskettes, 2DD; 2HD; and 2ED., with a back-up of raw materials of
over 2 Million diskettes awaiting production...

To order from single pack to volume quantities, email John
Schattin The listed prices DO NOT include shipping. But how heavy
is a box of floppies anyways?

Resistor Network by 95A Floppy Controller Bourns 4816P-002 -103 (bussed 10k ohm) Spec sheet HERE.
* Marked 2.88MB
Floppy Drives I just noticed that the 2.88 floppy drive in one of my
PS/2 machines has an asterisk (*) printed on the top side of the blue eject
button. Anybody has a clue as to what that might indicate? Is it just there
for looks?

From Peter The drives with the asterisk are those for 35/40, 56/57
and 76/77 - but *not* for 85/90/95. Should be a 64F4148, while the "others"
use a 64F0204. They differ slightly in the pinout and can damage
the planar on earlier Mod. 90 / 95. (Ed.
I'm using an asterisk 2.88 on my 9590. Note
that this is a later planar!)

Hi Al !
>9595 floppy is FRU 64F0204. Floppy I have that is mounted to the sled
is FRU 64F4148. Can I use this floppy on my 9595/8595 without fear?
That 64F4148 is the 35/40, 56/57, 76/77 FDD. If you really
like your 95 you *do not* try it in there. A team mate once did it ...
and it took us some days to solder in a new FDD-controller ... (main problem
was to find one at first)
I cannot figure out *exactly* what caused the mess, but
it has to do with the "security features" available on the 95 - and the
corresponding pins on the 56 - 77 being not present and set to GND. For
the older 8595 IBM published a warning, that use of the inappropriate FDD
could permanently damage the sysboard.

I whipped out my asterix marked FRU 64F4148. It's a Mitsubishi
MF356F-899MF. I just pulled my stock 2.88 from my Bermuda planar 9577-
it is a 64F4148 as well, BUT the Mitsubishi model is MF356C-799MF. First
postulation of the "Law of the Asterix" (you heard it here first, folks!)
is that the MF356F is the model that is incompatible with early 90s/95s.
As noted above, I have used the " * " floppy on a 9590 with
no unusual results. I figure that there must be a more primitive floppy
controller used on the 35/40 etc. systems. I do not have one of these to
check. Anyone with the answer, please tell
me!

Visual Differences Between M356C and M356FFrom Peter
BTW: the most obvious difference between Mitsu MF356C-799
and -899 is that -799 has a longer upper cover and the connector on the
left side (looking at the rear), while the -899 has a shorter upper cover
and the connector on the rear right side.
So they differ a lot through the mechanism (different
position of the head actuator stepper motor). For the electronics part
- I can't say.

Third Floppy
Connector Purpose> I noticed that the diskette drive connects to the motherboard using
some sort of strange connector. It appears to be about 44 pins or
so (compared to the SCSI connector), and the ribbon cable has *3* plugs
coming off it.
I never heard of anyone putting 3 diskette drives in a
machine (let alone a PS/2), and diskette drives use 30 (?) pins.
So what are the extra pins and connector for?

From Peter
The Mod. 56 / 57 / 76 / 77 / 85 / 90 / 95 use a somewhat
different FDD-connector on the planar. They have the Type-3 FDD-interface,
which also supports 2.88MB drives ("Media-Sense Drives"). The third connector
is for a very odd ITBU Internal Tape Backup Unit, which was a slightly
modified IRWIN 120MB tape. The machine supports only 2 FDDs - as usual.
Ed.Configuring
The 82077 For Tape Drive Mode The FDD-plugs are 34-pins (2 x 17), only the planar connector
is a bit strange 44-pins. This type of interface contains also lines for
security control, i.e. in connection with the "Electronic Eject 2.88MB
FDD", which can be locked and password protected.
Tried to find a pinout of the connector but haven't found
any at the moment ...

System Reports 165-
But Is the Floppy Working?From Tim Clarke>b) the floppy controller/drive/cable is suspect and needs looking
at. However, one would have expected a 601 error is things were really
bad.

Peter Responds- Not always. A disfuntional FDD may as well cause a 165.
"It is configured - but does not respond". If the heads stuck, do not pass
Track-00 tests or have RDATA stuck high or such you will surely get a 600-series
error. But if the drive has a "DC leak" and simply appears as absent it
is judged as "device missing but still present in the configuration".

8580 34 Pin
Floppy Drives From Fred Spencer These pin style diskette drives can be sub-divided into
two sub-groups. The original model 8580 drives are identified by the P/N
90X6766. I have seen these drives labeled as manufactured by Mitsubishi,
Alps Electric and YE Data. Later models were produced for the 8595 and
they are identified by the P/N 72X6112 or 1619618 and also sometimes accompanied
by the FRU # 64F0162 , which is also the FRU # reported in the HMM (October
1994) for both the 8580 and the 8595. HOWEVER, I have discovered that although
the 8595 drives (FRU #64F0162) will work on the 8580, the 8580 drives (P/N
90X6766) will NOT work on the 8595!!
The drives with FRU # 64F0162 have also been labeled as manufactured by
Mitsubishi, Alps Electric and YE Data.

Disabling
Floppy under Setup Even if you use the selectable boot and remove the 1.44,
A: drive from the boot sequence, there is a "safety" device that always
looks at the A: drive for a Reference Diskette. If there is a Reference
Diskette in the drive it will override "selectable boot"
OS/2 Floppy
Devices After the installation of OS/2 Warp and OS/2 Warp Fullpack,
CONFIG.SYS file contains two diskette-driver statements: IBM1FLPY.ADD and
IBM2FLPY.ADD. Only one of the drivers is loaded; the other just takes up
disk space. On MCA machines, you need IBM2FLPY.ADD. You may delete IBM1FLPY.ADD
NOTES: HERE* IBM1FLPY.ADD with /MCA works on the IBM PS/2 Micro Channel
systems.
* If installation is from DMF diskettes, use IBM1FLPY.ADD /MCA for
PS/2 MCA systems.

OS/2 Warp with WIN-OS/2
V300 Microsoft has confirmed they have changed thier compression
utility for windows products now shipping. The type of compression is not
recognized by OS/2 3.X on some older PS/2's. For example, some model 80,
70 and 65 machines.A programming error was found but will not be corrected.
It is a permanent restriction..
Local Fix
1. In config.sys
rem basedev=ibm2flpy.add
and use
basedev=ibm1flpy.add /mca
2. If above does not work then use following instead,
BASEDEV=IBM1FLPY.ADD /MCA /A:0
/U:0 /F:1.44MB /CL:AT

Media formats supported

MEDIA
SIZE

CAPACITY

SECTORS
PER TRACK

NO. OF

TRACKS

DATA RATE
(KBPS)

UNFORMATTED

FORMATTED

3.5 in

1.0MB

720KB

9

80

250

3.5 in

2.0MB

1.44MB

18

80

500

3.5 in

4.0MB

2.88MB

36

80

1000

5.25 in

0.5MB

360KB

9

40

300/250

5.25 in

1.6MB

1.20MB

15

80

500

Floppy Cable Pinout The diskette drive cable converts a 2- by 22-pin connector
on the system board into three 2- by 17-pin connectors for attaching internal
diskette drives. The cables pass control and data signals between the diskette
drive controller on the system board and the drives. They also provide
the power to each drive.
Note The 3.5-inch drives are required
to support media-sensing.

Floppy Planar
Pinouts

System board 44 pin connector pinout
(95A and Lacuna Planars)

Pin

Signal

Pin

Signal

1

-2nd drive installed

23

Ground

2

Data rate select 1

24

-Write enable

3

+5 V dc

25

Ground

4

Drive type ID 1/Drive status 1

26

-Track0

5

Ground

27

Media type 0/Drive status 2

6

+12 V dc

28

-Write protect

7

Ground

29

Ground

8

-Index

30

-Read data

9

Drive Type 0/Drive status 0

31

Ground

10

Reserved

32

-Head 1 select

11

Ground

33

Data rate select 0

12

-Drive select 0

34

Diskette change

13

Ground

35

Drive select 1

14

-Security command 0

36

Ground

15

Ground

37

-Security command 1

16

-Motor enable 0

38

Ground

17

Media type 1/Drive status 3

39

-Motor enable1

18

-Direction in

40

-Drive select 2

19

Ground

41

Ground

20

-Step

42

-Security command 2

21

Ground

43

Ground

22

-Write data

44

-Motor enable 2

34-Pin Header Interface

34-Pin Header (Non-media sense)

34-Pin Header (Media Sense)

Pin

Signal

Pin

Signal

Pin

Signal

Pin

Signal

1

Ground

2

-HD select

1

Ground

2

Data rate select

3

+5v DC

4

Drive Type
ID 1

3

+5v DC

4

Drive type ID 1/ Drive Status1

5

Ground

6

+12v DC

5

Ground

6

+12v DC

7

Ground

8

-Index

7

Ground

8

-Index

9

Ground

10

Reserved

9

Drive type ID 0

10

Reserved

11

Ground

12

-Drive select

11

Ground

12

-Drive select

13

Ground

14

Reserved

13

Ground

14

-Security Command

15

Ground

16

-Motor enable

15

Ground

16

-Motor enable

17

Ground

18

-Direction in

17

Media type 1/ Drive status 3

18

-Directionin

19

Ground

20

-Step

19

Ground

20

-Step

21

Ground

22

-Write data

21

Ground

22

-Write data

23

Ground

24

Write enable

23

Ground

24

-Write enable

25

Ground

26

-Track 0

25

Ground

26

-Track 0

27

Ground

28

-Write protect

27

Media type ID 0/ Drive status 2

28

-Write protect

29

Ground

30

-Read data

29

Ground

30

-Read data

31

Ground

32

-Head 1 Select

31

Ground

32

-Head 1 select

33

Ground

34

-Diskette change

33

Data rate select

34

-Diskette change

2.88 Floppy
to Clone Hack Just when you thought it couldn't be done... This is not
a 100% reliable way to hack the 2.88, BUT it shows that a strong possibility
exists.

From Sören Hedlund Since Febr I`ve tested with Sony MP-F40W-03 - and
still working on these machines, so I dont beleive there is a reliability
problem. Yes, 1.44 disk works fine, but not 720 - you loose about 5% when
formatting. However, I also had to make a circuit to make these Sony MP-F40W-03
to work properly with all three formats.

So if BIOS support 2.88 it does not mean it will work, the I/O
- chip must support it as well.

From Joseph Realmuto Jr The first is a 386-40 with a SIDE4 HP
multi-IO card(2.88MB capable floppy controller). Since this machine does
not have built-in 2.88MB support I had to use a TSR which updates the computer's
bios. The floppy controller on the card is capable of 1 Mb/sec data
rate. I
connected pins 34, 32, 30, 28, 26, 24, 22, 20, 18, 16, 12, 8, and 2
on the P/S2 floppy to the corresponding pins on the controller. I
left pins 4, 6, 10, and 14 on the floppy unconnected. Pin 3 of the
floppy was connected to +5V and pin 11 to ground. The floppy is a
Sony MP-F40W-03 connected as the B drive(the A drive is a standard 1.44
MB). The floppy reads, writes, and formats 2.88MB media. I can also
format 1.44MB media to 2.88MB without drilling an extra hole in it.
In fact, all media is automatically formatted at the drive's native capacity
unless forced with the /F switch. I was not able to get a Mitsubishi
MF356F-899MF drive to work on this machine (pins 26 and 34 seemed to oscillate,
and the computer said there was a seek error).
The second is a Packard Bell Pentium
machine with an Intel Triton chipset and an on- board 2.88MB capable floppy
controller. I used the above Mitsubishi floppy(again as the B drive)
and this time simply used an edge card adaptor which connects only the
top (even-numbered) pins,
and pin 1(ground). I added +5V on pin 3 by soldering a wire from
one of the hard drive power plugs. Again, this floppy works just
as well as the one on the 386 machine. It also seems to automatically
format at its native capacity regardless of which meda is actually in the
drive
unless forced with the /F switch.
It seems that pins 4, 10, and 14 can be left
either connected or unconnected(I recommend leaving unconnected).
Pin 6 should be either connected to pin 6 on the controller (which is an
N/C on clone controllers) or left unconnected. It should never be
connected to +12V even though this is in the pinout for the P/S2 floppy
for two reasons: 1)+12V is not used at all by the floppy drive
2)On some (Sony MP-F40W-15) pin 6 is DENSITY SELECT 0 and putting +12V
on a 5V logic line can fry the drive, controller, and possibly even the
motherboard.
As a last note, the 1.44MB media seems to
work well at 2.88MB. It formats error-free and seems to hold data
with no problem. I am doing some long-term testing to see if it will
retain data. At this time I do not recommend putting anything important
on these media. Please e-mail
me if you know of anybody who has tested this long term.

From David Beem As I am building up from the basics I am not having
too much trouble so far. Having learned not to assume on my or anyone's
theories I am slowly gaining information to see if I can pull this off.
I pulled out my Model 35SX, disconnected the 1.44M & connected the
spare (non-"*") 2.88 drive. After the expected 16x error I have it configure
itself & I am up and running with a 2.88Mb A: drive on a 386SX-20 computer.
Cool. Even like the guy said on your page that he was able to format a
standard HD disk as EHD with no complaints. Mine differed in that I had
to tell it with the /F:2.88 switch, otherwise it formatted it as 1.44Mb
(that was expected, but not *assumed* on my part).
I am using some pretty cheap bulk floppies too.
I don't know how long the information will last, but it is good to know
I can test the EHD media without having to find the exact diskette out
there. The Model 35SX uses a 82077 controller as well. As luck would have
it I also have an ISA Adaptec 1542 SCSI board with an onboard 82077 floppy
controller too. I can cross-check the IBM planars to it too see the pinout
changes.

Sony Board With the 1.44Mb PS/2 floppy drives IBM moved one
ground and one unused pin to put the 5 & 12VDC power on the 34-pin
connector. By my references they seem to have inverted a half-dozen control
signals too, but left them in the same relative position on the connector.
Modifying the Sony board with 3 circuit trace cuts and 3 jumpers to account
for the power connections at least allows the clone to power up. The Motor
Enable signal (one of the ones on the "twist" of the cable) is not inverted,
so it spins the drive up when a read from the floppy is given. The stepper
moter doesn't move though because that is one of the inverted signals.
I am going to see which buffer chip is used to invert
the signals between the Adaptec board and the IBM planars. There is probably
a riser with the correct buffer chip(s) I can assemble to do the task with
a little work. At least at the drive end the connector is pretty much the
same. What I have seen is that at the IBM planar end the Model 35, 40,
& 53 have a 40-pin connector and the Model 56, 57, 76, & 77 have
a 44-pin connector. I will figure out the pinouts for those too.

FIFO Mode The diskette drive controller uses
a FIFO buffer to enhance DMA transfer operations. The FIFO buffer
is used in the data transfer phase only, and its operation is transparent
to programs.

Removable Media
Security The diskette drive controller in
this system supports the optional 2.88MB enhanced diskette drive, which
has a media-security feature. This diskette drive supports Lock, Unlock,
and Eject commands; the Lock command inhibits diskettes from being removed
or inserted. Additionally, if the privileged-access password is set and
the diskette drive is in the boot path, the drive is automatically locked.

FRUs I have seen for the 2.88MB enhanced diskette
drive 92F0132, 92F0129, and I saw 82G1888 mentioned as well.

Secure Media Mode The secure media mode allows the
diskette drive to receive enhanced commands. These commands provide a means
of controlling access to the media in the diskette drives. Through
these commands, programs can eject a diskette or disable the mechanism,
which inhibits media from being removed or inserted.

To determine whether the mode and commands are
supported for a specific drive: 1. With the enhanced-command bit set to
1, test the state of the drive type (1,0) signals by reading the Drive
Status register.
Note For
info on enhanced-command bit, refer to System Control Port C
(Hex 007C).2.
With the enhanced-command bit set to 0, retest the state of the signals.
If the signals change to a binary 11, the mode and commands are supported
for that drive.

2.88MB Electronic
Eject Floppy

0 Eject with eject button
or sofware
1 Eject via software ONLY

An optional 2.88 MB diskette drive with security features is available
on some IBM PC Server systems. The diskette drive is a 3.5-inch,
one-inch high drive with media sense capability for the standard diskette
capacities of 720 KB, 1.44 MB, and 2.88 MB. It can read and write
data up to a formatted capacity of 2.88 MB, while maintaining read and
write capability with 720 KB and 1.44 MB diskette drives.
A control signal has been added to the diskette interface
that supports LOCK, UNLOCK, and EJECT commands issued by the operating
system. If the privileged-access password is not set, the diskette
is unlocked during POST. If the password is set, the boot process
does not unlock the diskette drive unless it is the designated IPL source.
an operating system utility. For SCSI devices, there is a proposed
standard UNLOCK command. In this case, the operating system will
control the LOCK command if the privileged-access password is set.
Access to the unlocking function with specific user authorization can be
controlled by secured system software.
In the event of power loss, the system retains its state
(secured or unsecured) independent of the state of the battery. A
diskette can be inserted in the drive, but it cannot be removed if the
power is off. When the drive is turned on and locked, the media cannot
be inserted or removed.

Enhanced
2.88MB Floppy Security Circuitry>1. Do all floppy controller chips have the ability
to pulse the leading edge of the of the security cmd signal? No. Only the later machines
support the security functions. It has been offered for the 9595 and 9585
at least. The EE 2.88MB drive comes in two "flavours": 92F0129 for all
9585 and 9595A, 92F0132 for 35/40, 56/57 (all), 76/77 (all) For the later group I can tell,
that the 35/40 and 8556/8557 have no security features integrated, most
likely the 9556/9557 and "Bermuda" 9576/9577 lack the feature too. The
FDD interface on these machines is a bit different from those on the "Servers".
However: the Server 77i had these security features mentioned in early
flyers. So it appears as if the "Lacuna" machines *have* the appropriate
additional controller logic. (Ed. The
82077SL FD controller has the extra circuitry that supports EE)>2. Is this a hardware function of the controller? Yes. But requires BIOS support.>3. Can this be controlled by software (thru
BIOS) on any controller? There was
a tool I cannot recall the name from, which could "lock" the EE-FDD function.
You could neither insert a Floppy when it is empty, nor pull one out if
there is one in the drive. I think they use a logic gate programmed on
the controller to stop the motorized eject / load function.

Tim ClarkeHi Louis, I think what the announcement
(and Peter et al.) talked about was software to *cause* the floppy to eject
*not* prevent/disable the feature, although I won't swear to this. I would
think the physical switch is your only option for that. I have the
'electronic eject' 5.25" slimline floppy in one of my 95s and none of the
PC-DOS 7 DRVLOCK /on, DRVLOCK /off or EJECT utilities accept it (B:) as
a supported drive. And, having thought about it ***there ain't no signal
lines to control this on the floppy interface***. So, perhaps you should
get a microswitch and patch that into the circuit, then mount the microswitch
somewhere devious. Or, even sneakier, figure out if any of the drive select
2/3 or motor enable 2/3 signals are actually passed through the ribbon
but not connected on the floppy drive's PCB circuitry and use one as 'gating
control' signal for the eject signal.

>The *electronic* eject drive is like the standard
push button drive. SONY made both of them. The EE drive allows
you to lock the floppy disk in the drive by flipping the eject button disable
switch on the side of the drive. Unfortantly the program to software eject
the disk via the OS is missing in action ...

The DISKETTE.DGS diagnostics
"overlay" tests the "security features" of the electronic diskette drives
when possible. A bit of reverse engineering might reveal what is needed
for recreation of these utilities. However, doesn't PC-DOS v7/2000 have
the DRVLOCK and EJECT commands? More fodder for the dedicated hacker.

Peter It has - but it fails with the EE-FDD
as far as I can tell. At least when using it in a Lacuna. As far as I can
tell they have been intended for CD-ROMs and MODs. DRVLOCK de-activates
the eject button and EJECT forces a media ject on them. *That* is known
to work under PC-DOS 7.0 with a CD-ROM installed ... I use EJECT recently
on my last PC-DOS survivor.

From Ernst Fueloep With OS/2 you can use the security
features for the enhanced 2.88 diskette drive from the diskette icon in
the drives folder. Just press the right mouse button and you will get options
for "Lock disk", "Eject disk" and "Unlock disk". Make sure the security
switch on the diskette drive is set to 1. You can find this switch on the
right side of the drive.

Electronic Eject
Commands

Lock Drive
Disables the load-and-eject mechanism. The drive will not eject a
loaded diskette, nor will it load a diskette. (Depending on the characteristics
of the drive, it may load the diskette and immediately try to eject it). Note Allow
500 mS after an Eject Media command before issuing Lock Drive cmd.Unlock Drive Enables
the load-and-eject mechanism, which allows diskettes to be removed from
and inserted into the selected drive.Eject Media Same
as pressing the eject button on the front of the drive; it causes
the drive to eject a diskette. This command is ignored if the drive is
locked.

To issue an
enhanced command: Set the value in the data-rate-select
bits (in the Data Rate Control register) at the positive-going edge of
the -security cmd signal. 1. Select the drive and save the state
of the data-rate-select bits. 2. Ensure that the System Control Port
C is available (bit 7 will be 0). 3. Set the enhanced-command bit to 0 (bit
0 of the System Control Port C). 4. Set the data-rate-select bits to the
desired command. 5. Set the enhanced-command bit to 1. 6. Restore the data-rate-select bits to
the desired data rate.

NoteIf
the drive is deselected before the enhanced-command bit is reset to 1,
the drive does not perform the command.